Year	Percent
1960	2.97901
1961	2.64062
1962	2.50375
1963	2.2116
1964	2.05052
1965	1.76847
1966	1.5096
1967	1.21676
1968	1.12184
1969	1.11822
1970	1.30641
1971	1.50431
1972	1.68472
1973	1.6236
1974	1.24574
1975	0.6619
1976	0.057
1977	-0.4896
1978	-0.5907
1979	-0.23891
1980	0.57571
1981	1.57035
1982	2.20368
1983	2.71877
1984	2.7291
1985	2.39409
1986	2.08815
1987	1.80696
1988	1.74039
1989	1.82588
1990	2.21822
1991	2.52615
1992	2.67805
1993	2.77968
1994	2.79975
1995	2.62501
1996	2.507
1997	2.41258
1998	2.18853
1999	1.8983
2000	1.55572
2001	1.18719
2002	0.87229
2003	0.64165
2004	0.52653
2005	0.51373
2006	0.53109
2007	0.51834
2008	0.55523
2009	0.56199
2010	0.62727
2011	0.62821
2012	0.76892
2013	0.77739
2014	0.8283
2015	0.91549
2016	1.00489
2017	1.04553